Related papers: Nonlinear response of 2DEG in the quantum Hall reg…
We propose a two-dimensional electron gas (2DEG) system in which an external magnetic (B) field with a small chirality is applied to provide a topological U(1) U(1) gauge field that separates conduction electrons of opposite spins in the…
The well-established symmetry relations for linear transport phenomena can not, in general, be applied in the non-linear regime. Here we propose a set of symmetry relations with respect to bias voltage and magnetic field for the non-linear…
We consider the full nonequilibrium response of a mesoscopic capacitor in the large transparency limit, exactly solving a model with electron-electron interactions appropriate for a cavity in the quantum Hall regime. For a cavity coupled to…
Observations of electron-hole asymmetry in transport through graphene devices at high magnetic field challenge prevalent models of the graphene quantum Hall effect. Here, we study this asymmetry both in conventional magnetotransport and in…
We introduce a new mechanism that produces a Hall-like response in time-reversal-invariant materials, driven entirely by geometric effects. Specifically, we demonstrate that a tilted potential interface causes electron wave packets to…
Magnetic-field-induced phase transitions were studied with a two-dimensional electron AlGaAs/GaAs system. The temperature-driven flow diagram shows the features of the $\Gamma$(2) modular symmetry, which includes distorted flowlines and…
We study transport properties of the helical edge channels of a quantum spin Hall (QSH) insulator, in the presence of electron-electron interactions and weak, local Rashba spin-orbit coupling. The combination of the two allows for inelastic…
We report magnetotransport measurements in a HgTe quantum well with an inverted band structure, which is expected to be a two-dimensional (2D) topological insulator. A small magnetic field perpendicular the 2D layer breaks the time reversal…
Can a generic magnetic insulator exhibit a Hall current? The quantum anomalous Hall effect (QAHE) is one example of an insulating bulk carrying a quantized Hall conductivity and other insulators (with zero Chern number) present zero Hall…
With the two-band continuum model, we study the broken inversion and time-reversal symmetry state of electrons with finite-range repulsive interactions in bilayer graphene. With the analytical solution to the mean-field Hamiltonian, we…
We report transport measurements in HgTe-based quantum wells with well width of 8 nm, corresponding to quantum spin Hall state, subject to in-plane magnetic field. In the absence of the magnetic field the local and nonlocal resistances…
We prove that the predicted charge transfer state in symmetric bilayers of two dimensional electron gases is always unstable at zero bias voltage, due to interlayer correlation and/or tunneling. This is most easily seen by resorting to a…
Two dimensional electron gases (2DEGs) realized at GaAs/AlGaAs single interfaces by molecular-beam epitaxy (MBE) reach mobilities of about 15 million cm^2/Vs if the AlGaAs alloy is grown after the GaAs. Surprisingly, the mobilities may drop…
We study the Hall constant in a homogeneous two-dimensional fluid of correlated electrons immersed in a perpendicular magnetic field, with special focus on the regime of low carrier density. The model consists of a one-band tight-binding…
A band gap for electronic states in crystals governs various properties of solids, such as transport, optical and magnetic properties. Its estimation and control have been an important issue in solid state physics. The band gap can be…
The transversal and longitudinal resistance in the quantum Hall effect regime was measured in a Si MOSFET sample in which a slot-gate allows one to vary the electron density and filling factor in different parts of the sample. In case of…
A new type of disorder-driven electronic percolation transition is found for two-dimensional electron gas (2DEG), based on a quantum cellular automaton model. This transition is shown to be accompanied with a metal-insulator transition, as…
We investigate the nonlinear regime of charge and energy transport through Coulomb-blockaded quantum dots. We discuss crossed effects that arise when electrons move in response to thermal gradients (Seebeck effect) or energy flows in…
Transport measurements are performed on InAs/GaSb double quantum wells at zero and finite magnetic fields applied parallel and perpendicular to the quantum wells. We investigate a sample in the inverted regime where electrons and holes…
Recent transport experiments have established that two-dimensional electron systems with high-index partial Landau level filling, $\nu^{*} =\nu - \lbrack \nu \rbrack$, have ground states with broken orientational symmetry. In a mean-field…